The only part of this that I can speak about is the transmission. The 4ZE1 comes with a much stronger transmission than the MSG transmission in your LUV. It is a MUA-5T and is used with engines as large as their 3.1L V6.
I've been told that this transmission won't fit in a 2nd gen LUV without enlarging the transmission tunnel, or doing a body lift. I assume the same would be true with a 1st gen LUV.
Also, it uses a hydraulically operated clutch, so if your truck has a cable operated clutch, you'd need to plan for that.
Jack
_________________
'83 Isuzu P'up Diesel LS - Original Owner
JoeIsuzu@IsuzuPup.comIsuzuPup.com